Piston.



R ALLEN.

PISTON.

APPLICATmN mw DE :.30.1914.

l ,1 88,876 Patented June 27, 1916.

4 SHEETS-SHEET H. ALLEN.

PiSTON.

APPLICATION mso DEC. 30. 1914.

Patented June 27, 1916.

4 SHEETS-SHEET 2.

R. ALLEN.

Pls'ToN.

lon min DEC, 304 |914 PPLICM' Patented J une 27, 19H5 EETS- A lllliitllf'llillll' STATES PATENT OFFICE.

ROBERT ALLEN, OF CAVERSHAM, ENGLAND.

PISTON.

Specification of Letters Patent.

Patented June 27, 1 91 6.

Applicatan filed December 30, 1914. Serial No. 879,731.

uw in meridia t l! fir centering ring and piston vm-zeit the axis for the pui# 1 f wenn; ing the, 'piston or compensatfirwru iva-ar oi' the vision which oc is ell'ecnd by a at or near the d and transmitted le miams such radialiv sin 'Une een www; ring iuojrtorru the nain body poi'- mfn .of the piston and carry the packing rings or la: ciai'ae iront the packing.

ln one toria oi construction :is applied. to a box section piston rmifztiueufd with a hollow main body `portion oi parking ring earlier viii h a collar on the piston rod is clamped, wifi o5' [lie rod is bored axially and threaded to receive a conical plug and ring provided with suitable openings tor ill-y reception oi adjusting keys. l'he plug is, arranged to act on a rod or rods mounted to slide in radial openings in the head oi the piston rod. and bearing againstI the packing ring' carrier which in this case 'forms the centering ring. This ring also torni.y the hollow main body of the piston and mal bw f `t in one piece with an inner ring er millar which surround,-. the collar on the ni n rod and is connected ith the {rf-:id lemon ot thc body by radial webs wir loria hanpression stays, for the hol- ;.ca' la. lle latter case the adune' Y: Hear against the inner ring :ia-mw, but. when this is iwtprovided they ncridecl te act directly on the tread nuention is hereinafter described and movable end plates between' with reference to the accompanying drawings in which Figure 1 is an end elevation of a piston constructed according to this invention, one of the end plates being removed. Fig. 2 is a vertical section of the saine. Figs. 3 and 4 are similar views to Figs. l and 2 illustrating a modified form of construction. Figs.-

aad (i are detail viewsiillustrating in section and end elevation respectively one end ol a two part stud bolt, and its seatinff. Figs. 7 and 8 ai: sections through the ends of the piston rod and portions of the iston heads attached thereto, showing di erent ways of securing the parts ot the head in position on the rod.

Referring to Figs. 1 and the box section piston shown therein comprises end plates a, 11,1 fixed against a boss or enlargement i on the piston Aod and a hollow main body portion or packing ring carrier l which is adjustable in relation to the end plates a al and foi-nis the centering ring. Bolts c with countersunk heads and nuts are employed to secure the end plates together and to fix then] firmly against the body if and boss on the rod, the heads of the bolts being locked by pins c] or other means. The centering ring 'b is formed with seating grooves or recesses d for the packing rings e which are spring expanded rings of the pressure balanced type, and is connected by radial ribs f with an inner ring or collar y] which surrounds the collar or boss b on the piston rod` sullicient space or clearance beingleft between the boss I) and collar g to admit of the transverse adjustment of one relatively to the other as hereinafter described.

llxtinding inward for a suitable distance from the outer end of the piston rod is'a bored hole or recess z' intended to receive and guide the screw threaded adjusting plug j which is made of conical form for a portion of its) length and has an opening s for the insertion of a key for the adjustment of the plug. Rods Z, beveled at their inner ends bear against the plug j and also against the collar g f the centering ring, said rods being guided in radial holes in the piston rod. Where the collar g is not employed the rods Z may be extended to act directly on theeentering ring b1. IThe outer end plate a of the piston is bored centrally to enable the adjusting key .to be inserted into the adjusting pliig j in .the piston rod,

his opmng being" as ,hown in Figa I and when in pn `it10n may be held by a www Stud m, crews into the baas 'u' cnmr un 2,

1 i engages a .svrew is pxewnts the @Quien n g in bia Maasai/*43 he :for 1H will the', Fmg www mm; ing

n." "riff 

